.syntax unified .cpu cortex-m0plus .thumb #include "pico/asm_helper.S" // This macro tells the pico runtime to call __wakeup_gpio_latch very early in boot __pre_init __wakeup_gpio_latch, 00000 .section .data.wakeup_gpio_latch .global wakeup_gpio_state .align 4 wakeup_gpio_state: .word 0x00000000 .section .text .thumb_func __wakeup_gpio_latch: // Read GPIO state for front buttons and store movs r3, 0xd0 // Load 0xd0 into r3 lsls r3, r3, 24 // Shift left 24 to get 0xd0000000 ldr r1, [r3, 4] // Load GPIO state (0xd0000004) into r1 ldr r2, =wakeup_gpio_state // Load output var addr into r2 str r1, [r2] // Store r1 to r2 // Enable 3v3 pin on the badger ldr r1, =0x40014054 // GPIO control register 10 movs r2, 5 // SIO function str r2, [r1] // Set Enable 3v3 to SIO // https://github.com/raspberrypi/pico-sdk/blob/2e6142b15b8a75c1227dd3edbe839193b2bf9041/src/rp2_common/hardware_gpio/include/hardware/gpio.h#L96 str r2, [r1, 120] // Also set LED (25) to SIO ldr r2, =0x02000400 // Pins 25 and 10 str r2, [r3, 36] // Enable pins out str r2, [r3, 20] // Set pins high bx lr // Return